Checkers suitable for forming a checker work in a hot blast stove and method of forming same



0 United States Patent [1113,549,136

[72] lnventors Kenneth A. Bub; 2,172,714 9/1939 Schack et al 263/51 James M. Blackwood, Bethlehem, Pa. 2,493,458 1/1950 Koenig 263/51 1211 Appl. No. 737,529 2,577,170 12/1951 Walters 263/51 rifle d 315, 13: I FOREIGN PATENTS atente Assignee Bemlehem steel Corporation 766,713 7/1934 France 263/51 a corporation fb l Primary Examiner-John J. Camby Attorney-A. M. Griffin [54] 3 AND ABSTRACT: This invention relates to an improved checker METHOD OF FORMING SAME for hot blast stoves generally hexagonal in cross section, hav- 2 claims, 8 Drawing 38$ ing six side walls, parallel top and bottom surfaces, and a plurality of vertical parallel gas passages extending therethrough. 263/51 A plurality of vertical parallel grooves are provided at the corlllt- Cl F23| 15/02 ners of the side walls and at a midpoint of the side walls. The Search top and bottom surfaces are provided a plurality of pro jeetions and recesses generally triangular in cross section. [56] References cued Other checkers generally pentagonal in cross section and half UNITED STATES PATENTS hexagonal checkers required to form a checker-work in a hot l,792,663 2/ 1931 Strack 263/51 blast stove are described.

CHECKERS SUITABLE FOR FORMING A CHECKER WORK IN A HOT BLAST STOVE AND METHOD OF FORMING SAME BACKGROUND OF THE INVENTION the columns of checkers above the point of failure to collapse thereby destroying a major portion, if not all, of the checkerwork in the stove. The pile up of crushed and damaged checkers causes clogging of the passages. As a result the stove must be taken out of service, the collapsed checkerwork removed and a new checkerwork prepared. Attempts to prevent column collapse have included using square or rectangularly shaped checkers having lugs and recesses on two surfaces. However, the checkerwork formed by these checkers is difficult to support at the ring wall. The standard hexagonal checker, well known in the art, is adequate but cannot be laid in overlappinglayers and is susceptible to complete collapse of the checkerwork if one checker near the bottom of the stove is crushed or damaged.

It is therefore the object of this invention to provide checkers with can be laid up in overlapping layers and which I can be locked in place thereby preventing collapse of the checkerwork upon failure of one checker.

SUMMARY OF THE INVENTION Broadly, the checker of the invention has a polygonal cross section with a plurality of sidewalls, top and bottom surfaces, a plurality of equispaced gas passagesextending therethrough, grooves formed at the midpoint and corners of the sidewalls and a pluralityof projections and depressions in the top and bottom surfaces whereby the checkers may be laid up in over lapping and interlocked configuration.

BRIEF DESCRIPTION OF THE DRAWINGS horizontal sections of several layers-of the checkers in a hot blast stove. 8

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now in more detail to the drawings, FIG. 1 shows a layer of the checkers as they appear in one horizontal layer of a hot blast stove formed by laying checkers 10, 20, 40 adjacent to each other. 'Tuming now to FIG. 2 which shows a checker 10 of the invention to have the shape of a hexagon having six sidewalls 11, which if extended could form six corners l2, and parallel top 17 and bottom 17a (not shown) surfaces. Axially aligned with the sidewalls 11 is a central gas passage 13 which may be circular in cross section. Disposed concentrically around the central gas passage 13 and equispaced therefrom, are a plurality of additional parallel gas passages 14. Each of the comers 12 of the checker 10 are provided with a groove 15. Each sidewall 11 is provided with a groove 16 midway between the comers 12. All the grooves 15 and 16 have a generally semicircular cross section. The gas passages 13 and 14 and the grooves 15 and 16 are aligned in the checker such that their central axes are equidistant from each other. By positioning the gas passages 13 and 14 andgrooves 15 and 16 in this fashion, it is possible to lay the checkers in overlapping fashion and maintain continuous gas passages through the checkerwork, in a'hot blast stove. The top 17 and bottom 17a surfaces of the checker are provided with three projections 18 and three depressions 19 in the general shape of an equilateral triangle. In laying-up the checkers the projections 18 of one checker fit into the depressions 19 in upper or lower checkers. The interlocking feature, namely the mating of the projections 18 of one checker with the depressions 19 of other checkers, prevents lateral movement of the checkerwork thereby preventing collapse of adjacent columns if one checker should fail.

Turning now to FIG. 3, the top 17 and bottom 17a surfaces of the checker 10 are seen in profile. Note that a projection 18 on the top surface 17 can be mated with a depression 19 on the bottom surface 17a of the checker immediately above.

FIG. 4 shows another configuration of the checker used to form the checkerwork in a hot blast stove. This checker 20 has the form of a pentagon having one flat backwall 21, two parallel sidewalls 22 and 23, two converging sidewalls 24 and 25. It has a top surface 17', a bottom surface 17a (not shown), and gas passages 13a and 14a and grooves 15a and 16a similar to checker 10 as described above. Additionally, the sidewalls 22 and 23 are provided with grooves 22a and 23a. The projections 18a and depressions 19a are generally triangular in cross section while projection 18b and depression 19b are four sided in cross section.

As noted in the above description of the generally hexagonal shape 10, the gas passages 13 and 14 and the grooves 15 and 16 are aligned in the checker such that their central axes are equidistant from each other. This is true of all the checkers and for clarity sake is shown in FIG. 4. The distances denoted by lines a, b and c between gas passages 13a, 14a and grooves and 16a are equidistant.

The checker 30 shown in FIG. 5 is a smaller version of checker 20 having four vertical gas passages 13b and 14b and grooves 15b and 16b as described for checker 20. FIG. 6 shows a checker 40 which is a half of a hexagonal checker. The prime numbers designating corresponding gas passages and grooves as shown in FIG. 2. This form is necessary to complete the checkerwork in a hot blast stove. It is necessary to have these forms of checkers so that complete horizontal layers may be formed in the hot blast stove and that the layers may be arranged in staggered configuration to form a checkerwork having continuous gas passages in a hot blast stove.

FIGS. 7 and 7a show the manner in which the checkers of the invention are laid up to form a checkerwork in a hot blast stove. The checkerwork thus formed is stable and will not collapse if any checker fails prematurely as noted above.

We claim:

1. A checker having six sidewalls andparallel top and bottom surfaces and of generally hexagonal cross section, characterized by:

a. a central passage extending longitudinally therethrough;

b. a semicircular longitudinal groove in the center of each sidewall;

c. a longitudinal groove at the corner of each pair of adjacent sidewalls;

d. six additional longitudinal passages surrounding said central passage;

e. eachcontiguous pair of said additional passages being parallel to an adjacent sidewall; and

f. each top and bottom surface having three raised generally triangular portions and three depressed generally triangular portions, each of said triangular portions having a base coextensive with a sidewall and extending inwardly of said sidewall.

2. A checkerwork for use in a hot blast stove comprising a plurality of horizontal parallel layers of checkers laid up one upon another in interlocking relationship, said checkers having a hexagonal cross section and'having parallel top and bottorn surfaces each of said surfaces having raised and depressed portions, said portions having a base coextensive with a sidewall and extending inwardly of said wall, said interlocking gas passage extending longitudinally c. a longitudinal groove at the comer of each pair of adjacent sidewalls;

d. additional gas passages surrounding said central passage;

and

e. each contiguous pair of said additional gas passages being parallel to an adjacent sidewall of said checker. 

